Differentiating microcystic meningioma from atypical meningioma using diffusion-weighted imaging.

PURPOSE: Microcystic meningioma (MCM) appears similar to atypical meningioma(AM) as per conventional diagnostic imaging. However, considering their different recurrence rate and prognosis, accurate differential diagnosis is essential for determine the appropriate treatment strategy. The aim of the study was to differentiate MCM from AM by diffusion-weighted imaging (DWI), in order to provide the basis for accurate preoperative diagnosis. METHODS: The preoperative clinical data, conventional MRI and DWI data of 15 MCM and 30 AM cases were retrospectively analyzed. The average apparent diffusion coefficient (ADCmean), minimum ADC (ADCmin) and normalized ADC (nADC) between MCM and AM were compared using two sample t-tests. The value of ADCmean, ADCmin and nADC in the differential diagnosis of MCM and AM were calculated by the receiver operating curve (ROC) analysis. RESULTS: The ADCmean (1.06 ± 0.10 vs 0.80 ± 0.11 × 10-3 mm2/s; P < 0.001), ADCmin (0.99 ± 0.10 vs 0.74 ± 0.12 × 10-3 mm2/s; P < 0.001) and nADC (1.45 ± 0.17 vs 1.07 ± 0.17; P < .0001) were significantly higher in MCM compared to AM. ADCmean of 0.91 × 10-3 mm2/s showed an optimum area under the ROC curve of 0.967 ± 0.022, and distinguished between MCM and AM with 86.67% sensitivity, 100% specificity and 88.89% accuracy. In addition, its positive and negative predictive values were 96.29% and 77.78% respectively. CONCLUSIONS: DWI can differentially diagnose MCM and AM, and ADCmean is a potential quantitative tool that can improve preoperative diagnosis of both tumors.

Plain Computed Tomography With Spectral Imaging Findings of Early Cerebral Ischemia.

PURPOSE: To investigate the findings of plain spectral computed tomography (CT) with multiparameter of early cerebral ischemia. PATIENTS AND METHODS: Thirty-three patients with suspected early cerebral ischemia who received a one-stop CT examination (plain scan with spectral CT imaging mode, CTP and CTA) of the brain were enrolled in this study. No clear lesion was observed in any patient on the plain CT. However, the CTA displayed evidence of vascular stenosis and the CTP displayed a corresponding low perfusion area consistent with early cerebral ischemia. Regions of interest were placed in the abnormal perfusion regions and the contralateral symmetric regions on plain CT. Then, the CT value of the monochromatic images (70 kV), the slope of the spectral HU curve, blood (iodine), iodine (water), and water (iodine) concentrations were measured. A paired t-test was performed for data comparison. The receiver operating characteristic curve was used to evaluate diagnostic performance. RESULTS: The CT values of the ischemic regions at 70 keV, the spectral HU curve, water, and blood values of the ischemic measurements were slightly lower than those of the contralateral symmetric regions (P < .05). Monochromatic images at 70 keV had the highest area under the curve value, and the sensitivity and specificity were 90.0% and 63.0%, respectively. CONCLUSION: The difference of monochromatic CT values, spectral HU curve, and basic material concentrations between the early cerebral ischemia region and the contralateral symmetric region on spectral CT imaging may provide a reference with the diagnosis of early cerebral ischemia.

Apparent Diffusion Coefficient to Evaluate Adult Intracranial Ependymomas: Relationship to Ki-67 Proliferation Index.

BACKGROUND AND PURPOSE: There are important differences in the treatment and prognosis of adult intracranial low-grade ependymomas (grade II) versus anaplastic ependymomas (grade III). We evaluated the value of the apparent diffusion coefficient (ADC) for differentiating these two tumors and further investigated the relationship between ADC values and the Ki-67 proliferation index. METHODS: Clinical and preoperative magnetic resonance imaging data of 35 cases of adult intracranial ependymomas were retrospectively analyzed, including 20 low-grade ependymomas and 15 anaplastic ependymomas. The minimum ADC (ADCmin), average ADC (ADCmean), and normalized ADC (nADC) were compared between the two groups. Receiver operating characteristic curves were drawn to evaluate the differentiating accuracy of ADC values. The Ki-67 proliferation index of the solid tumor components was also measured to explore its relationship with ADC values. RESULTS: The ADCmin (.89 ± .17 vs. .66 ± .09 × 10-3  mm2 /second), ADCmean (.98 ± .21 vs. .72 ± .11 × 10-3 mm2 /second), and nADC (1.38 ± .31 vs. 1.02 ± .18 × 10-3  mm2 /second) were significantly higher in adult intracranial low-grade ependymomas than anaplastic ependymomas cases (all P < .05). ADCmean best distinguished the two groups, with an area under the curve value of .900. Using .716 × 10-3  mm2 /second as the optimal threshold, the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the two groups were 66.7%, 100%, 85.7%, 100%, and 80%, respectively. ADCmin (r = -.490), ADCmean (r = -.449), and nADC (r = -.425) showed significant negative correlations with the Ki-67 proliferation index (all P < .05). CONCLUSIONS: ADC values can differentiate adult intracranial low-grade ependymomas and anaplastic ependymomas, which could improve the preoperative diagnostic accuracy of these two tumors and guide their treatment.

Inhibition of ceramide synthesis reverses endothelial dysfunction and atherosclerosis in streptozotocin-induced diabetic rats.

OBJECTIVES: To explore the effect of myriocin on EDVD and atherosclerosis in diabetic rats. METHODS: Rats were fed with a high-fat/high-sucrose/high-cholesterol diet (20% sucrose, 10% animal oil, 1.0% bile salt and 2.5% cholesterol) (hereinafter defined as diabetic groups) or Purina Rodent Chow (NC group), the former was intervened with low dose streptozotocin (30 mg/kg) after feeding 1 month to make diabetic model. The NC group was intervened with citrate buffer and the diabetic rats were intervened with myriocin (0.3 mg/kg Qod) (MTD group) or just solvent (DC group) for 14 weeks. The EDVD, thickness of fatty deposition under endothelium, ceramide, PI3K/PKB/eNOS, NO and other vital parameters were measured after the rats sacrificed. RESULTS: In DC group, the ceramide contents in serum and aorta increased, the EDVD was impaired, the fatty deposition under endothelium increased, and the phosphorylation of PI3K/PKB/eNOS and NO release decreased all compared with the NC group (P<0.05). Compared with the DC group, the ceramide contents in MTD group decreased, the EDVD ameliorated, the fatty deposition diminished, and PI3K/PKB/eNOS phosphorylation and NO release (P<0.05) increased. CONCLUSIONS: After treated with myriocin, the EDVD in diabetic rats has been improved by increasing PI3K/PKB/eNOS phosphorylation and NO release, and meanwhile the atherosclerosis has reversed.